diff options
| -rw-r--r-- | include/linux/kallsyms.h | 11 | ||||
| -rw-r--r-- | kernel/kallsyms.c | 123 | ||||
| -rw-r--r-- | kernel/module.c | 3 |
3 files changed, 93 insertions, 44 deletions
diff --git a/include/linux/kallsyms.h b/include/linux/kallsyms.h index 849043ce4ed..1cebcbc28b4 100644 --- a/include/linux/kallsyms.h +++ b/include/linux/kallsyms.h @@ -12,6 +12,10 @@ /* Lookup the address for a symbol. Returns 0 if not found. */ unsigned long kallsyms_lookup_name(const char *name); +extern int kallsyms_lookup_size_offset(unsigned long addr, + unsigned long *symbolsize, + unsigned long *offset); + /* Lookup an address. modname is set to NULL if it's in the kernel. */ const char *kallsyms_lookup(unsigned long addr, unsigned long *symbolsize, @@ -28,6 +32,13 @@ static inline unsigned long kallsyms_lookup_name(const char *name) return 0; } +static inline int kallsyms_lookup_size_offset(unsigned long addr, + unsigned long *symbolsize, + unsigned long *offset) +{ + return 0; +} + static inline const char *kallsyms_lookup(unsigned long addr, unsigned long *symbolsize, unsigned long *offset, diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c index 342bca62c49..eeac3e313b2 100644 --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -69,6 +69,15 @@ static inline int is_kernel(unsigned long addr) return in_gate_area_no_task(addr); } +static int is_ksym_addr(unsigned long addr) +{ + if (all_var) + return is_kernel(addr); + + return is_kernel_text(addr) || is_kernel_inittext(addr) || + is_kernel_extratext(addr); +} + /* expand a compressed symbol data into the resulting uncompressed string, given the offset to where the symbol is in the compressed stream */ static unsigned int kallsyms_expand_symbol(unsigned int off, char *result) @@ -155,6 +164,73 @@ unsigned long kallsyms_lookup_name(const char *name) return module_kallsyms_lookup_name(name); } +static unsigned long get_symbol_pos(unsigned long addr, + unsigned long *symbolsize, + unsigned long *offset) +{ + unsigned long symbol_start = 0, symbol_end = 0; + unsigned long i, low, high, mid; + + /* This kernel should never had been booted. */ + BUG_ON(!kallsyms_addresses); + + /* do a binary search on the sorted kallsyms_addresses array */ + low = 0; + high = kallsyms_num_syms; + + while (high - low > 1) { + mid = (low + high) / 2; + if (kallsyms_addresses[mid] <= addr) + low = mid; + else + high = mid; + } + + /* + * search for the first aliased symbol. Aliased + * symbols are symbols with the same address + */ + while (low && kallsyms_addresses[low-1] == kallsyms_addresses[low]) + --low; + + symbol_start = kallsyms_addresses[low]; + + /* Search for next non-aliased symbol */ + for (i = low + 1; i < kallsyms_num_syms; i++) { + if (kallsyms_addresses[i] > symbol_start) { + symbol_end = kallsyms_addresses[i]; + break; + } + } + + /* if we found no next symbol, we use the end of the section */ + if (!symbol_end) { + if (is_kernel_inittext(addr)) + symbol_end = (unsigned long)_einittext; + else if (all_var) + symbol_end = (unsigned long)_end; + else + symbol_end = (unsigned long)_etext; + } + + *symbolsize = symbol_end - symbol_start; + *offset = addr - symbol_start; + + return low; +} + +/* + * Lookup an address but don't bother to find any names. + */ +int kallsyms_lookup_size_offset(unsigned long addr, unsigned long *symbolsize, + unsigned long *offset) +{ + if (is_ksym_addr(addr)) + return !!get_symbol_pos(addr, symbolsize, offset); + + return !!module_address_lookup(addr, symbolsize, offset, NULL); +} + /* * Lookup an address * - modname is set to NULL if it's in the kernel @@ -167,57 +243,18 @@ const char *kallsyms_lookup(unsigned long addr, unsigned long *offset, char **modname, char *namebuf) { - unsigned long i, low, high, mid; const char *msym; - /* This kernel should never had been booted. */ - BUG_ON(!kallsyms_addresses); - namebuf[KSYM_NAME_LEN] = 0; namebuf[0] = 0; - if ((all_var && is_kernel(addr)) || - (!all_var && (is_kernel_text(addr) || is_kernel_inittext(addr) || - is_kernel_extratext(addr)))) { - unsigned long symbol_end = 0; - - /* do a binary search on the sorted kallsyms_addresses array */ - low = 0; - high = kallsyms_num_syms; - - while (high-low > 1) { - mid = (low + high) / 2; - if (kallsyms_addresses[mid] <= addr) low = mid; - else high = mid; - } - - /* search for the first aliased symbol. Aliased symbols are - symbols with the same address */ - while (low && kallsyms_addresses[low - 1] == kallsyms_addresses[low]) - --low; + if (is_ksym_addr(addr)) { + unsigned long pos; + pos = get_symbol_pos(addr, symbolsize, offset); /* Grab name */ - kallsyms_expand_symbol(get_symbol_offset(low), namebuf); - - /* Search for next non-aliased symbol */ - for (i = low + 1; i < kallsyms_num_syms; i++) { - if (kallsyms_addresses[i] > kallsyms_addresses[low]) { - symbol_end = kallsyms_addresses[i]; - break; - } - } - - /* if we found no next symbol, we use the end of the section */ - if (!symbol_end) { - if (is_kernel_inittext(addr)) - symbol_end = (unsigned long)_einittext; - else - symbol_end = all_var ? (unsigned long)_end : (unsigned long)_etext; - } - - *symbolsize = symbol_end - kallsyms_addresses[low]; + kallsyms_expand_symbol(get_symbol_offset(pos), namebuf); *modname = NULL; - *offset = addr - kallsyms_addresses[low]; return namebuf; } diff --git a/kernel/module.c b/kernel/module.c index 7c77a0a9275..7f60e782de1 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2040,7 +2040,8 @@ const char *module_address_lookup(unsigned long addr, list_for_each_entry(mod, &modules, list) { if (within(addr, mod->module_init, mod->init_size) || within(addr, mod->module_core, mod->core_size)) { - *modname = mod->name; + if (modname) + *modname = mod->name; return get_ksymbol(mod, addr, size, offset); } } |